I thought I'd relay this information as some may find it useful. I recently purchased a QuNexus and at first was bit disappointed as some keys were not responding well. However, once I tried a few different synths I found that specific ones were actually quite amazing and the touch on all keys was accurate, consistent and with zero latency.

I would consider the QuNexus to be more than a toy. It's an actual musical instrument and a pretty decent one at that.

The only drawback for Linux users is their software is only Windows or OSX. The editor loads in WINE but up to now have not been able to recognize the device. I have been able to use VirtualBox to detect and modify settings.